1. Technical Field
The present invention generally relates to integrated circuits and in particular to leakage current in integrated circuits. Still more particular, the present invention relates to compensation of leakage current in integrated circuits.
2. Cross Reference to Related Patent Application
The present application relates to Application Serial No. (RPS9 20060191US1); “Automatic Self-Adaptive Keeper System With Current Sensor For Real-Time /on Line Compensation For Leakage Current Variations”; Filed Jul. 3, 2007; Inventor: Zhibin Cheng and assigned to the assignee of the present invention. The referenced patent application is incorporated in its entirety in the present application.
3. Description of Related Art
The use of keeper circuit arrangements to compensate for leakage current at an internal node of a storage device is well known in the prior art.
For example, U.S. patents 6,844,750 B2, 7,002,375 B2 U.S. published patent applications U.S. 2004/189337A1 and U.S.2005/01046121 all describe keeper type circuit arrangements. Although, these circuit arrangements work well for intended purposes they share a common set of design characteristics which are not necessarily desirable for some situations or use. The design characteristics are that the keeper circuit arrangements are digitally controlled, over design to compensate for maximum leakage conditions and compensate by varying the physical dimension of the keeper. The physical dimension of the keeper may be varied by increasing/decreasing the number of devices in the keeper circuit.
As a consequence, there is a need to provide a keeper circuit arrangement that do not share the undesirable common design characteristics set forth above, yet still provide compensation on a real time basis for all leakages including leakage resulting from process variation relating to the process use to manufacture the chip.